MySQL Learning Note: concat, CONCAT_WS, group_concat--string connection

in MySQL, there are 3 main functions for string concatenation:

• Concat (x, y,...)
• Concat_ws (delimiter, x, y,...)
• Group_concat (distinct xxx ORDER by Asd/desc yyy separator ' delimiter ')

First, concat function

The concat () function is used to concatenate multiple strings into a single string

Format: concat (STR1,STR2,...)

--MySQL concat ()--SELECTCONCAT ('I',' Love','Somebody'); # IlovesomebodySELECTCONCAT ('I',NULL,'Somebody'); #NULLSELECTCONCAT (14.4); #14.4

Attention:

If any one of the arguments is NULL, the return value is null;
Returns a non-binary string if all arguments are not binary strings;
Returns a binary string if any twos binary string is included;

MySQL Learning Note: concat, CONCAT_WS, group_concat--string connection